How to improve switch case that returns true/false or throw an exception?

Question

Given the following code:

private boolean isBlahTrue(final BigDecimal status) {

        switch (status.intValue()) {

            case 1:
            case 2:
            case 3:
                return true;

            case 5:
            case 6:
            case 7:
                return false;

            default:
                throw new MyAppRuntimeException("Status unknown!");
        }
    }

My question is: Is this good or bad practice?

Logic is:

1, 2, 3  --> true
5, 6, 7  --> false

But anyway one could think about that a simple IF would do the stuff too, like

if (1,2,3) {true}, else {false}

.

But then I would not check if the status is e.g. 4 (which must lead to an exception).

I tried some solutions, like contains, but the code doesn't improve.

Any ideas that I could try?

Answer 1

I would suggest using a Map in this case.

something like

Map<Integer, Boolean> statusChecker = new HashMap<>();
statusChecker.put(1, true);
statusChecker.put(2, true);
... 
statusChecker.put(5, false);
...

Now you can do the checking

if(!statusChecker.contains(status)) {
   throw RuntimeException("invalid status");
} else {
   return statusChecker.get(status);
}